Woody Woodward, a spokesman for the San Antonio Fire Department, said the fire was started by some construction workers welding in the hotel's stairwell. Some sparks went into the stairwell's vent and flames shot up from about the third floor to the fifth.

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Firefighters on Wednesday, Dec. 13, responded to a fire at the Grand Hyatt hotel in downtown San Antonio.

Media: San Antonio Express-News

Firefighters extinguished the blaze quickly, he said.

The hotel's sprinkler system turned on on the affected floors during the fire.

"That's probably going to be the biggest damage they had," Woodward said.

There were no evacuations at the hotel, though some residents went to the lobby when alarms sounded. No injuries were reported.